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排序方式: 共有4618条查询结果,搜索用时 29 毫秒
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J. M. Vance M. A. Pericak-Vance R. C. Elston P. M. Conneally K. K. Namboodiri R. S. Wappner P. L. Yu John M. Optiz 《American journal of medical genetics. Part A》1980,7(2):131-140
Serum and/or plasma samples from 360 Whites and 126 Blacks were assayed for activity of the lysosomal hydrolase α-N-acetyl-D-glucosaminidase (NAG). The samples from the Blacks had an increased mean (0.50 nm/ml/min) and standard deviation (0.30 nm/ml/min) compared to those from the Whites (0.29 nm/ml/min and 0.10 nm/ml/min, respectively). After loge transformation and admixture analysis, it was possible to demonstrate the presence of 3 distributions of NAG activity in Blacks and at least 2 in Whites. Segregation analysis of the NAG activity of 29 White half-sib twin families indicated that a genetic model for the inheritance of NAG activity provided a better fit (P < 0.01) with the data than the “environmental” model. Thus, the study suggests the presence of a genetic polymorphism for NAG activity in Black and White populations. The presence of alleles for high and low NAG activity in the normal population could lead to incorrect interpretation of serum carrier tests for Sanfilippo syndrome, type B. 相似文献
64.
Deckardjanatpour K Muller W Chodosh L Gardner H Marquis S Coffey R Cardiff R 《International journal of oncology》1997,11(2):235-241
The mammary glands of control FVB and mice with MTV-LTR promoted transgenes were stained using immunohistochemistry to detect neu expression. Neu expression in the terminal end buds of developing mammary glands and during early pregnancy in FVB mice was confirmed by in situ hybridization. Neu was expressed in all tumors from mice with the neu transgene but not in tumors expressing transforming growth factor alpha (TGF alpha) or polyoma virus middle T (PyV-MT). Neu was also expressed sporadically in non-neoplastic mammary cells of transgenic neu mice. However, most mammary cells expressing neu were dysplastic. The differential expression of the neu transgene has important implications for the interpretation of transgenic biology. 相似文献
65.
BackgroundMindfulness interventions can improve psychological distress and quality of life (QoL) in cancer survivors. Few mindfulness programs for cancer recovery exist in Southeastern U.S. The primary objective of this study was to assess the feasibility of a modified mindfulness-based stress reduction (MBSR) program for breast cancer patients in Birmingham, Alabama. The secondary objective was to explore potential program effects on mindfulness skills and QoL.MethodsThis study was a prospective, quasi-experimental feasibility study conducted over 10 months at a university hospital. Feasibility was achieved if 80% of eligible patients screened enrolled in the study and 70% of enrolled patients attended all 8 program sessions. Effectiveness was estimated by changes in mindfulness and QoL indicators measured with validated scales administered at 3 time points and assessed with a non-parametric Friedman test. Sessions included meditation, yoga, and an attention practice called body scan. There were 3 groups of 2–5 patients.ResultsThe sample totaled 12 patients. Forty-four percent (12/27) of eligible patients enrolled in the study, and two out of 12 enrolled patients completed 8 program sessions, resulting in 16.7% (2/12) retention. However, more than half (66.7%) of participants completed at least 7 sessions. Between baseline and 8-week follow-up, patients demonstrated statistically significant improvements in distress, general wellbeing, and fatigue-related QoL.ConclusionsFeasibility objectives were not achieved. However, a majority of participants (66.7%) completed 7 of 8 program sessions. Program effects were promising for distress, fatigue, and wellbeing. Results warrant further research on MBSR-like programs for breast cancer patients in Alabama. 相似文献
66.
《Academic pediatrics》2022,22(5):769-776
ObjectiveTo examine whether patterns of body mass index (BMI) percentile gains across childhood predict BMI percentile, overweight and obesity, waist circumference, and elevated or prehypertensive blood pressure at age 15.MethodsTrained technicians in the Study of Early Child Care and Youth Development assessed children's weight and height from birth to 15 years and waist circumference and blood pressure at age 15 (n = 1132). Children's BMI percentile trajectories from age 2 to age 13 along with 28 demographic and social covariates were used to predict BMI percentile, waist circumference, overweight, obesity, and elevated or prehypertensive blood pressure. Linear and logistic regressions were used to predict BMI percentile, overweight, obesity, waist circumference, and elevated or prehypertensive blood pressure.ResultsChildren were classified into one"?>1 of 4four"?> BMI percentile trajectories: “low stable” (28.4%), “low-to-high” (11.8%), “median stable” (29.0%), and “high rising” (30.7%). Children in trajectory classes characterized by persistent above average BMI percentile or by periods of rapid BMI percentile gains were more likely than their peers to experience poor weight and elevated or prehypertensive outcomes in adolescence. Trajectory class membership explained substantially more variance in adolescent health outcomes than demographic covariates alone. Estimated maternal BMI was a key independent predictor of adolescent outcomes.ConclusionsDifferent patterns of BMI percentile gains, namely those with rapid gains or persistently above average BMI percentile, from ages 2 to 13 predicted weight, waist circumference, and elevated or prehypertensive blood pressure at age 15, above and beyond demographic and social characteristics. 相似文献
67.
Bone Mineral Density and Androgen Levels in Elderly Males 总被引:4,自引:0,他引:4
Rapado A Hawkins F Sobrinho L Díaz-Curiel M Galvao-Telles A Arver S Melo Gomes J Mazer N Garcia e Costa J Horcajada C López-Gavilanes E Mascarenhas M Papapietro K López Alvarez MB Pereira MC Martinez G Valverde I García JJ Carballal JJ García I 《Calcified tissue international》1999,65(6):417-421
To clarify the relationship of sex male hormones and bone in men, we studied in 140 healthy elderly men (aged 55–90 years)
the relation between serum levels of androgens and related sex hormones, bone mineral density (BMD) at different sites, and
other parameters related to bone metabolism. Our results show a slight decrease of serum-free testosterone with age, with
an increase of follicle stimulating hormone (FSH) and luteinizing hormone (LH) in a third of the elderly subjects studied.
BMD decreased significantly with age in all regions studied, except in the lumbar spine. We found a positive correlation between
body mass index (BMI) and BMD at the lumbar spine and femoral neck (P < 0.001). No relationship was found (uni- and multivariate regression analysis) between serum androgens or sex hormone-binding
globulin (SHBG) and BMD. We found a positive correlation of vitamin D binding protein (DBP) and osteocalcin with lumbar spine
BMD and with BMI, DBP, IGF-1, and PTH with femoral neck BMD. In conclusion, there is a slight decline in free testosterone
and BMD in the healthy elderly males. However, sex male hormones are not correlated to the decrease in hip BMD. Other age-related
factors must be associated with bone loss in elderly males.
Received: 29 April 1997 / Accepted: 9 November 1997 相似文献
68.
Preliminary study of electrocautery smoke particles produced in vitro and during laparoscopic procedures 总被引:1,自引:0,他引:1
Background: The objective of this preliminary study was to describe the particles contained in cautery smoke produced during five laparoscopic procedures and verify the collection method during three laboratory experiments on ex vivo animal tissue.
Methods: A cascade impactor collected the smoke according to particle size, and particle weights were calculated on an electronic microbalance. Electron microscopic analysis and energy dispersive X-ray evaluation were used to determine particle morphology and elemental composition.
Results: The particles, distributed according to size on the seven rotating trays of the impactor, had diameters ranging from 0.05 to >25 m, with most being 0.1–1 m. In vitro experiments yielded more particles, especially larger (>5 m) ones, than the surgical procedures, because the cauterized specimens could be placed much closer to the cascade impactor in the laboratory environment, eliminating most obstacles to particle recovery. In the laparoscopic surgery patients, larger particles, because of their physical properties, were more likely to remain trapped in the abdomen or to drop off in the collection apparatus. Uniformly, two populations of particles were demonstrated—either large, irregular fragments (2–25 m) rich in carbon and oxygen, suggesting structural cellular components, or small homogeneous spheres (0.1–0.5 m) composed of sodium, magnesium, calcium, and potassium salts.
Conclusions: This study demonstrates the presence of breathable areosols and cell-size fragments in the cautery smoke produced during laparoscopic procedures. Their exact chemical composition and potential adverse effects for patients and personnel are not known. 相似文献
69.
Ventilation (E), end-tidal (P')co2 mixed venous Pco2 (Pco2andthe ventilatory response to carbon dioxide (E/Pco2) were measured before and within 90 min asgtermorphine 0.15 mg kg1 i.m. given to 17 adult patientsundergoing elective surgery under general anaesthesia. The hypothesisthat pastients with a low ventilastory response to carbon dioxideare more susceptible to the ventilatory depressant effecstsof morphine was tested. Morephine induced increases in PE'co2andPco2 were not correlasted witheither the slope or the position of the preinjection responseto carbon dioxide. Mean E/Pco2was depressed after morphine (P <0.05), but individual responsesvaried widely. Seven pastients whose control E/Pco2 was 9.9 litre min1kPa1 or lessdecreased E/Pco2 after morphine.In four patients, E/Pco2 increasedafter morphine; however, in each case, PE'co2 and Pco2 increased also. Morphine disphine displaced thecarbon dioxide response to the right (P < 0.001) but no correlationwas found between either the magnitude of the displacement orchange in slope and control E/Pco2.The results suggest that patients with a low value for E/Pco2 are not more susceptible tothe ventilatory depressant action of morphine. 相似文献
70.
Jacques Brisson Caroline Diorio Beno?t Masse 《Cancer epidemiology, biomarkers & prevention》2003,12(8):728-732
Mammographic breast densities are one of the strongest breast cancer risk factors. The two most frequently used classifications of breast densities are Wolfe's parenchymal pattern and the percentage of the breast with densities. In this analysis, associations of these two classifications with breast cancer risk were compared, and the dose response curve of risk with densities was examined. Three case-control studies were combined totaling 1060 cases with newly diagnosed breast cancer and 2352 controls. A single observer had assessed parenchymal pattern and percent density without any information on subjects. Relative risks (RRs) were estimated with logistic regression and spline functions adjusting for age and body weight. The two classifications were strongly correlated (r = 0.81, P = 0.0001). Breast cancer risk increased progressively with percent density reaching a 5-6-fold increase for women with 85% or more of the breast with densities compared with women with no density. In contrast, women with P2 or DY patterns had only a 2-3-fold increase in risk compared with women with N1 pattern. More importantly, among women with P2 or DY, RR varied substantially with percent density, whereas, among women with a given percent density, RR varied little with parenchymal pattern. Comparisons of multivariate models reveal that in the presence of parenchymal pattern, inclusion of percent density in the model improved the prediction of breast cancer risk (chi(2) = 35.5, P = 0.0082) but not the opposite (chi(2) = 1.1, P = 0.7662). These findings show that the percentage of the breast with densities provide more information on breast cancer risk than Wolfe's parenchymal patterns and that, once percent breast density is taken into account, no more information on breast cancer risk is given by assessing parenchymal pattern. 相似文献